Solar panels in space could cut Europe's renewable energy needs by 80%

Close, it was microwaves!

https://www.space.com/japan-space-based-solar-power-demonstration-2025

Microwave scattering is an absolute nightmare over that kind of distance. Even for much shorter distances, microwaves are only practical to transport over a couple of meters in a waveguide.

If its transmitting to a base station, we can assume it's in geosynchronous orbit, or about 22,000 miles from the surface. With a fairly large dish on the satellite, you could probably keep the beam fairly tight until it hit the atmosphere, but that last ~100 miles of air would scatter it like no tomorrow. Clouds and humidity are also a huge problem -- water is an exceptionally good absorber in most of the MW band.

I saw numbers reported for the transmission efficiency somewhere (will update this if I can find it again), and they were sub-30%. The other 70% is either boiling clouds on its way down, or missing the reviever on the ground and gently cooking the surrounding area.

Hoo boy that's pretty light on details about scale, there's a few buzz words in there too, I hope they can develop it enough to make it viable in large capacities.